High power COIL fiber transmission

Abstract

Up to 11 kW of CW laser power at a wavelength of 1.3 µm has been successfully coupled into a 20 meter long optical fiber. The present experiment aimed at the evaluation of COIL application for the decommissioning of nuclear installations was performed using the existing COIL facility at the DLR Lampoldshausen site. This facility is briefly described in terms of its main components and operating parameters. A customer designed optical system by the HighYag company is presented: it enables the propper coupling of the 1.3 µm radiation into a 1000 µm fiber and the appropriate delivery of the laser beam onto the workpiece. The transmission losses of the COIL radiation range between 15 and 20 % as deduced from online measurements. Cutting examples in stainless steel, concrete, and other materials are given and discussed.